Ruby Wax: Donald Trump hated me. I asked him questions that irritated him, then wondered why he was being a jerk

Ex-celebrity interviewer Ruby Wax, 60, wrote a show about her depression. Now, she has an MA in mindfulness-based cognitive therapy from Oxford.

What’s your new live show about? It’s based on the book Sane New World – about how your brain works. It’s a survival manual for the 21st century. It’s a tour of your brain – what to do with it, what’s going on with it and why we’re screwed. I talk about how we’re burning out because some of the chemicals that make us ‘go for it’ never shut down, which is why stress is expected to be the biggest killer by 2020.

You talk about neural plasticity – what is it? In the past, people thought we were stuck the way we are because of our genes, like a stamp, but now they’ve discovered neural plasticity. Gloria Gaynor’s going to have to change the lyrics to I Am What I Am because you aren’t what you are. Instead of saying ‘I’m a victim’ or ‘I’m aggressive’, like you’re a brand of soup, they’ve found it isn’t true and you’re only cornered or labelled when you do it to yourself. Neural plasticity means behaviours can be changed.

Has talking about your experiences with depression in your previous show had negatives consequences? Are you kidding? I toured the world and got to stay in great hotels. I might have lost work if I was still in TV – no one wants to take a risk on that, so I kept it quiet. But then Comic Relief put big posters of me in Tube stations, saying: ‘I have a mental illness.’ Then I wrote a show and pretended it was my publicity poster. I did the show in mental institutions, then it became a hit. I became so interested in how the brain works, I enrolled to study it at Oxford – that wouldn’t have happened if I was still yipping away doing a talk show.

Has the stigma around mental health issues improved? Things have changed. No one doubts the numbers now, that one in four people will experience a mental health problem. People still lose their jobs because they have depression. I’ve given talks at banks – some want to get ahead of the game. They’ve started giving people with depression time off to get better because it’s estimated £100billion is lost each year on absenteeism caused by some sort of mental problem.

You say you weren’t a very good actress. What were the low-lights? Playing a wench in a Royal Shakespeare Company production of Love’s Labours Lost with Alan Rickman. I was playing Michael Hordern’s girlfriend and he whispered: ‘I’m so ashamed,’ because my acting wasn’t correct. Later on, Alan Rickman said: ‘Maybe you should consider another career.’ He told me to write the way I talk and we’d do a show. I handed him 200 pages of madness, he edited it and directed my first solo show. I went on with the RSC for another couple of years and never really improved. Things wouldn’t have kept going for me as a Shakespearean actress.

Who didn’t you get on with when doing chat shows? There were a few that went wrong. Donald Trump hated me. There were times when I thought I was being charming but I was really being passive aggressive. I asked him questions that irritated him, then wondered why he was being a jerk – but I was pulling the jerkiness out of him. But others loved me. OJ Simpson was in love.

Is the celebrity TV interview format a bit clapped out? Graham Norton has the right personality for it – he can zap up a guest. I could do that only sporadically but I’d be with them for a few days, so I’d have enough time. You wouldn’t get that sort of access now.

Have you turned your back on showbiz? I didn’t turn my back but there was no way to keep going after 25 years – and I didn’t want to cling on by my toenails to get a panto. So I steered it another way and what I’m doing now is so interesting. I get to study and meet the experts and translate that material into a show.

What are you proudest of achieving? Getting on TED talks but idiots don’t know what TED talks are. If you don’t know, I’m not going to explain it. Usually when you perform in front of an audience, you think ‘they’re just people’ but with TED talks, it’s all geniuses – and they were listening to me, who knows nothing.

What lessons has your career in showbiz taught you? Get out when it’s time to and get another job before everyone drops you. It’s worked out for me but not everyone is as lucky.

Ruby tours Sane New World across Britain until the end of May. The paperback of the same name is out now. www.rubywax.net